Field
Exemplary embodiments relate to a touch display device. More particularly, exemplary embodiments relate to a touch display device that has sensing electrodes disposed on a single layer.
Discussion of the Background
A touch display device includes a touch panel. The touch panel generally includes sensing electrodes disposed in a matrix. The touch display device is largely classified into a mutual-capacitance type and a self-capacitance type depending on the disposition of the sensing electrodes and a method of sensing a user touch the display panel.
FIG. 1 is a diagram illustrating a portion of the existing self-capacitance type touch display device. Referring to FIG. 1, in the existing touch display device, five sensing electrodes 101, 102, 103, 104, and 105 are disposed on a single layer and each sensing electrode is connected to pads through separate wires. Each wire is directly connected to touch detection circuits (not illustrated) or is connected to the touch detection circuits through a demultiplexer (not illustrated).
In order to increase the accuracy of detecting touch inputs (i.e., the touch resolution) of a touch display having the same screen size, a larger number of smaller sensing electrodes must be disposed in the same area. As a result, the number of wires connected to sensing electrodes from the touch detection circuits correspondingly increase. In other words, 10 sensing electrodes require 10 wires and 20 sensing electrodes require 20 wires.
Space is limited in a touch display, especially a touch display having a touch panel with a single layer structure. The limited space means that there is a limit to the number of wires that the touch display can house. Thus, only a limited number of sensing electrodes may be included in such a touch display, thereby limiting the touch resolution of the device. Parasitic capacitance also occurs between the wires or between the wires and the sensing electrodes further complicating matters and decreasing the reliability of such touch displays.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.